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Plant source of cocaine is Erythroxylum coca. It has a potent stimulating action on central nervous system, producing a sense of euphoria and increased energy. Excessive dosage of cocaine causes hallucinations.

Cocaine has a potent simulating action on central nervous system producing a sense of euphoria and increased energy. Excessive dosage of cocaine causes hallucinations.

(c) suppression of brain function

Meissner’s corpuscles are small light pressure receptors found just beneath the epidermis in the dermal papillae.

Correct answer is (d) Coca

Sound waves entering the external auditory meatus fall on the tympanic membrane. This causes the ear drum to vibrate, and these vibrations are transmitted to the oval window through the three auditory ossicles. Since the tympanic membrane is 17-20 times larger than the oval window, the pressure exerted on the oval window is about 20 times more than that on the tympanic membrane.

This increased pressure generates pressure waves in the fluid of perilymph. This pressure causes the round window to alternately bulge outward and inward meanwhile the basilar membrane along with the organ of Corti move up and down. These movements of the hair alternately open and close the mechanically gated ion channels in the base of hair cells and the action potential is propagated to the brain as sound sensation through cochlear nerve.

(a) Erythroxylum coca

Eustachian tube acts as a ventilator and helps in equalising air pressure on the two sides of the tympanic membrane.

The lower end of each semicircular canal is swollen and it is called ampulla. Each ampulla has a sensory area known as crista ampullaris.

(d) A neuron is polarized only when the outer surface of the axonal membrane possess a negative charge and its inner surface is positively charged.

The sebaceous glands at the base of eyelashes are called Ciliary glands.

Skin is the sensory organ of touch and is also the largest sense organ. This sensation conies from millions of microscopic sensory receptors located all over the skin and associated with the general sensations of contact, pressure, heat, cold and pain. Some parts of the body, such as the finger tips have a large number of these receptors, making them more sensitive. 

Some of the sensory receptors present in the skin are:

• Tactile merkel disc is light touch receptor lying in the deeper layer of epidermis.
• Hair follicle receptors are light touch receptors lying around the hair follicles.
• Meissner’s corpuscles are small light pressure receptors found just beneath the epidermis in the dermal papillae. They are numerous in hairless skin areas such as finger tips and soles of the feet.
• Pacinian corpuscles are the large egg shaped receptors found scattered deep in the dermis and monitoring vibration due.to pressure. It allows to detect different textures, temperature, hardness and pain.
• Ruffini endings which lie in the dermis responds to continuous pressure.
• Krause end bulbs are thermoreceptors that sense temperature.

Balance is part of a sense called proprioception, which is the ability to sense the position, orientation and movement of the body. The organ of balance is known as the vestibular system which is located in the inner ear next to the cochlea.

The vestibular system is composed of a series of fluid filled sacs and tubules.These sacs and tubules contain endolymph and are kept in the surrounding perilymph. These two fluids, perilymph and endolymph, respond to the mechanical forces, during changes occurring in body position and acceleration.

The utricle and saccule are two membraiious sacs, found nearest the cochlea and contain equilibrium receptor regions called maculae that are involved in detecting the linear movement of the head.

The maculae contain the hair cells that act as mechanoreceptors. These hair cells are embeded in a gelatinous otolithic membrane that contains small calcareous particles called otoliths. This membrane adds weight to the top of the hair cells and increase the inertia.

The canals that lie posterior and lateral to the vestibule are semicircular canals; they are anterior, posterior and lateral canals oriented at right angles to each other.

At one end of each semicircular canal, at its lower end has a swollen area called ampulla. Each ampulla has a sensory area known as crista ampullaris which is formed of sensory hair cells and supporting cells. The function of these canals is to detect rotational movement of the head.

A tube called Eustachian tube connects the middle ear cavity with the pharynx. It helps in equalizing the pressure of air on either sides of the ear drum.

Melanocytes are the cells responsible for producing the skin pigment called Melanin.

(d) Organs of corti

(b) (ii), (iii) and (iv)

(d) Basal epithelial cells are sensitive portions of the taste.

(b) Neurilemma

The wax producing sebaceous glands in the external auditory meatus are ceruminous glands.

A small depression present in the centre of the yellow spot is called fovea centralis.

The yellow flat spot at the centre of the posterior region of the retina is called macula lutea. It is responsible for sharp detailed vision.

The process of cloning multiple copies of a gene is called gene cloning.

An embryonic cell having totipotency that can replicate indefinitely, transform into other types of cells, and serve as a continuous source of new cells. These cells are derived from inner cell mass of the blastocyst or the 4-8 cell stage of embryo.

CaCl₂ is known to increase the efficiency of DNA uptake to produce transformed bacterial cells. The divalent Ca²⁺ ions supposedly create transient pores on the bacterial cell wall by which the entry of foreign DNA is facilitated into the bacterial cells.

Most commonly used plant cloning vector "Ti" plasmid, or tumor-inducing plasmid. Found in cells of the bacterium known as Agrobacterium tumefaciens, normally lives in soil. Bacterium has ability to infect plants and cause a crown gall, or tumorous lump, to form at the site of infection. 

Ti plasmid - called T DNA - separates from the plasmid and incorporates into the host cell genome. This aspect of Ti plasmid function has made it useful as a plant cloning vector (natural genetic engineer). 

In molecular biology and microbiology, replica plating is a technique in which one or more secondary Petri plates containing different solid (agar-based) selective growth media (lacking nutrients or containing chemical growth inhibitors such as antibiotics) are inoculated with the same colonies of microorganisms from a primary plate (or master dish), reproducing the original spatial pattern of colonies.

The technique involves pressing a velveteen-covered disk, and then imprinting secondary plates with cells in colonies removed from the original plate by the material. Generally, large numbers of colonies (roughly 30-300) are replica plated due to the difficulty in streaking each out individually onto a separate plate. 

PCR is a cycle of three steps:

DENATURATION - the strands of the DNA are melted apart by heating to 95°C. 

ANNEALING - the temperature is reduced to ~ 55°C to allow the primers to anneal to the target DNA. 

POLYMERISATION/EXTENSION - the temperature is changed to the optimum temperature in order for the DNA polymerase to catalyse extension of the primers, i.e. to copy the DNA between the primers. 

The cycle is repeated over and over again - as many times as needed to produce a detectable amount of product (DNA).

Glycogen is called as animal starch.

Embryonic stem cells are pluripotent and depending upon the type of stimulus given, these cells can differentiate into about 200 different cell types present in the body of an adult human being. Thus ES have tremendous potential for use in regenerative medicine to generate organs and tissues for replacement of damaged or diseased ones in case of:

• Leukemia or cancerous blood cells. 
• Heart diseases, cardiac tissue damage.
• Paralysis (spinal cord injury)
• Alzheimer‘s, Parkinson‘s, Huntington‘s disease.
• Burns (damaged skin cells)

Cry IAc/Cry IIAb genes are incorporated in a cotton plant.

Nucleopolyhedrovirus is a genus of baculovirus.

They are species specific, have narrow spectrum insecticidal application and no negative impact on non-target organisms, hence they are considered good biocontrol agents.

Correct Answer is: (B) Eco RI

GAATTC is a restriction site for EcoR1 restriction enzyme. When EcoRI recognizes and cuts this site, it always does so in a very specific pattern that produces ends with single-stranded DNA “overhangs". This restriction enzyme has been isolated from species of E coli bacteria.

Source organism — Bacillus thuringiensis

Target pest — Cotton bollworms

a. cryIAc gene codes for a toxic insecticidal protein that controls the cotton bollworms.

b. This gene codes for a toxin that becomes active when ingested by the insect. The activated toxin binds to the surface of mid-gut epithelial cells thus creating pores which causes cell swelling and lysis, further leading to death of the insects.

a. cryIAc gene codes for a toxic insecticidal protein that controls the cotton bollworms.

b. This gene codes for a toxin that becomes active when ingested by the insect. The activated toxin binds to the surface of mid-gut epithelial cells thus creating pores which causes cell swelling and lysis, further leading to death of the insects.

The technique involves the use of a popularly known biopesticide Bt toxin produced by bacteria Bacillus thuriengiensis. Bt toxin protein when ingested by the insect gets converted to its active form due to alkaline pH of the gut. The activated toxin binds to the surface of midgut epithelial cells. It creates pores in these cells that cause swelling and lysis and eventually kills the insect. The genes (cry genes) encoding this protein are isolated from the bacterium and incorporated into crop plants like cotton. The proteins encoded by these cry genes control the pest. Specifically, cryIAc and cryIIAb control cotton bollworm (Helicoverpa armigera), an insect belonging to Lepidoptera which earlier used to destroy the whole crop.

Bacillus thuringiensis products are endotoxin which when ingested and released in the gut of the larvae of insect pest disrupts the insect gut lining thereby killing them.

Bacillus thuringiensis products are endotoxin which when ingested and released in the gut of the larvae of insect pest, disrupts the insect gut lining thereby killing them.

Gow, buffalo, goat, sheep, camel, horse, dog, cat etc. are the reared animals in our nearby area.

Nowadays, tractors are used for ploughing and sowing the seeds is True.

Production of insulin by rDNA techniques was achieved by an American company, Eli Lilly, in 1983. It prepared two DNA sequences corresponding to A and B chains of human insulin and introduced them in plasmids of E. coli for production. The A and B chains produced were separated, extracted and combined by creating disulfide bonds to form human insulin.

Onam is celebrated in kerala.

Moisture in ground and epidemic of organisms are the main problems in grain storage.

Food and mouth diseases (FMD), mastitis, lupus etc.

Due to the excessive uses of chemical fertilizers, there is a gradual increase in the’ productivity of the land. They may cause health problems like headache, skin disease, stomach related problems, restlessness etc.

Due to the moisture in the ground and continuous evil activities of the epidemic organisms, the grains get spoiled.

1. (Pushkar) 

2. (bags) 

3. (domestic animals) 

4. (horse).

Correct answer is mixed fractions are not converted into improper fraction.